Displaying 20 results from an estimated 6000 matches similar to: "logistic regression - exp(estimates)?"
2010 Feb 05
3
metafor package: effect sizes are not fully independent
In a classical meta analysis model y_i = X_i * beta_i + e_i, data
{y_i} are assumed to be independent effect sizes. However, I'm
encountering the following two scenarios:
(1) Each source has multiple effect sizes, thus {y_i} are not fully
independent with each other.
(2) Each source has multiple effect sizes, each of the effect size
from a source can be categorized as one of a factor levels
2008 Sep 26
2
ANOVA between & within variance
hi,
is there an option to calculate the 'within' & 'between' group variances
for a simple ANOVA (aov) model (2 groups, 1 trait, normally distr.) ?
or do I have to calculate them from the Sum Sq ?
thanks for your time and greetings,
gregor
--
Gregor Rolshausen
PhD Student; University of Freiburg, Germany
e-mail: gregor.rolshausen at biologie.uni-freiburg.de
tel. :
2011 Jul 19
1
notation question
Dear list, I am currently writing up some of my R models in a more
formal sense for a paper, and I am having trouble with the notation.
Although this isn't really an 'R' question, it should help me to
understand a bit better what I am actually doing when fitting my
models!
Using the analysis of co-variance example from MASS (fourth edition, p
142), what is the correct notation for the
2012 Dec 30
3
Odds Ratio and Logistic Regression
Dear All,
I am learning the ropes about logistic regression in R.
I found some interesting examples
http://bit.ly/Vq4GgX
http://bit.ly/W9fUTg
http://bit.ly/UfK73e
but I am a bit lost.
I have several questions.
1) For instance, what is the difference between
glm.out = glm(response ~ poverty + gender, family=binomial(logit),
data=mydata)
and
glm.out = glm(response ~ poverty * gender,
2003 Oct 23
1
Variance-covariance matrix for beta hat and b hat from lme
Dear all,
Given a LME model (following the notation of Pinheiro and Bates 2000) y_i
= X_i*beta + Z_i*b_i + e_i, is it possible to extract the
variance-covariance matrix for the estimated beta_i hat and b_i hat from the
lme fitted object?
The reason for needing this is because I want to have interval prediction on
the predicted values (at level = 0:1). The "predict.lme" seems to
2008 Sep 30
1
Version 2.7.2 GUI acts awkward?
hi,
I am running R 2.7.2 Windows - recently the GUI-windows (for example to
"change directory" or "read in R-scripts") do not open - well, they
open, but close down directly afterwards. I can't select a directory or
file ...
I tried re-installing R - same problem again.
does anybody have an idea?
thanks
gregor
--
Gregor Rolshausen
PhD Student; University of
2011 Feb 15
1
quick question about binary data
Dear all,This is both an R and a statistics question. I want to test whether males and females of a given species tend to co-occur in a given sampling unit more frequently than expected by chance. I'm thinking about using a binomial distribution with p as the sex ratio of the entire population. So, even though the population sex ratio is close to 50:50, each sampling unit would have
2018 Jan 09
3
barplot_add=TRUE
Dear R users
aim
Barplot of insect trap catches (y variable trapcatch) at one specific station (variable FiBL_Hecke) from week 1-52 ( x variable week).
It works well using the function tapply (sum trapcatch per week, males and females not separated), however, I intend to separate the y variable trapcatch in males and females (variable m_w: m and w)
problem
I used the function "add" to
2012 Nov 05
1
Post hoc tests in gam (mgcv)
Hi.
I'm analysing some fish biological traits with a gam in mgcv. After several
tries, I got this model
log(tle) = sexcolor + s(doy, bs = "cc", by = sexcolor) +log(tl)
sexcolor is a factor with 4 levels
doy is "day of year", which is modeled as a smoother
tl is "total length of the fish"
The summary of this models is (only parametric coefficientes):
Parametric
2011 Dec 01
1
logistic regression - glm.fit: fitted probabilities numerically 0 or 1 occurred
Sorry if this is a duplicate: This is a re-post because the pdf's mentioned
below did not go through.
Hello,
I'm new'ish to R, and very new to glm. I've read a lot about my issue:
Warning message:
glm.fit: fitted probabilities numerically 0 or 1 occurred
...including:
http://tolstoy.newcastle.edu.au/R/help/05/07/7759.html
2008 Feb 06
1
Nested ANOVA models in R
Hi,
I'm trying to work through a Nested ANOVA for the following scenario:
20 males were used to fertilize eggs of 4 females per male, so that
female is nested within male (80 females used total). Spine length
was measured on 11 offspring per family, resulting in 880
measurements on 80 families.
I used the following two commands:
summary(aov(Spinelength ~ Male*Female))
and
2004 Jul 20
5
Precision in R
Greetings.
I'm trying to recreate in R some regression models I've done in SAS,
but I'm not getting the same results. My advisor suspects this may be
due to differences in precision between R and SAS. Does anyone know
where I can find specifications for R's type double? (It doesn't seem
to be in the R Language Definition.) Thanks in advance for any help
anyone can
2010 Mar 11
2
as.integer and indexes error
Hello All,
I would like to report the following bug or maybe you can explain if I am
wrong.
I am sampling from two different populations with weights. The two
populations have the same age groups and I want to distinguish where I am
sampling from. That is why I am using a matrix such as:
matrix
age.group Male Females Weight.Males Weight.Females
1 1.1
2011 Mar 10
3
Fw: random sampling steps in R with replacement
Please note is with replacement
From: taby gathoni <tabieg@yahoo.com>
To: R help <r-help@r-project.org>
Sent: Thursday, March 10, 2011 11:53 AM
Subject: [R] random sampling steps in R
Dear all,
Could someone assist me in random sampling steps/code in R? I have a main sample of 42 males and 165 females and I want to come up with about 1000 samples of 20 males and 20 females from
2010 Dec 09
3
hi have a question about merging.
this is the problem:
load this R data frame over the internet and save it to your hard drive.
http://rss.acs.unt.edu/Rdoc/library/twang/data/raceproling.RData
please show how to save a dataset of males only (the variable male=1) to a new dataframe. Then do the same thing for females (male=0). Then show how to recombine the two datasets to belike the original one except that the female
2009 Jan 14
5
How to compute p-Values
Hello.
How can I compute the Bootstrap p-Value for a one- and two sided test, when I have a bootstrap sample of a statistic of 1000 for example?
My hypothesis are for example:
1. Two-Sided: H0: mean=0 vs. H1: mean!=0
2. One Sided: H0: mean>=0 vs. H1: mean<0
I hope you can help me
Thanks in advance
Regards,
Andreas
2004 Dec 15
2
how to fit a weighted logistic regression?
I tried lrm in library(Design) but there is always
some error message. Is this function really doing the
weighted logistic regression as maximizing the
following likelihood:
\sum w_i*(y_i*\beta*x_i-log(1+exp(\beta*x_i)))
Does anybody know a better way to fit this kind of
model in R?
FYI: one example of getting error message is like:
> x=runif(10,0,3)
> y=c(rep(0,5),rep(1,5))
>
2005 Mar 22
1
List of tables rather than an extra dimension in the table or (l)apply(xtabs)
I'm not sure how to best explain what I am after but here goes. I have a data frame with 2 geographical factors. One is the major region the other is the component regions.
I am trying to process all the regions at the same time without using "for". So I need (think, I do) a list of matrices each structured according to the number of subregions within each region.
So is there a
2010 Oct 07
2
first post and bootstarpping problems
Hello to all R users,
I use R for a year now and am dealing with geometric morphometrics of deer skulls. Yes, I am a biologist and my math skills are just beginning to brush up. To cut to the chase...
I have two groups in my data (males and females) and my data is in a simple vector form. Now I need a bootstrap test for this value
szc1 <- ((mean(maleCent)-mean(femaCent))^
2004 Aug 05
1
cross random effects (more information abuot the data)
Dear friends,
I have asked last few days about cross-random effects
using PQL, but I have not receive any answer because
might my question was not clear.
My question was about analysing the salamander mating
data using PQL. This data contain cross-random effects
for (male) and for (female). By opining MASS and lme
library. I wrote this code
sala.glmm <- glmmPQL(fixed=y~WSf*WSM,